Sorry about that teaser title. This isn't a tip for bad guys, this is for the good guys: DON'T use geotagging on your smartphone. Cheryl Rodewig explains it in Geotagging poses security risks at Army.mil, and it's a warning that the GPS feature in the typical camera phone records the user's location, and some social media services publish that information. Excerpt:
Someone with the right software and the wrong motivation could download the photo and extract the coordinates from the metadata.
Warren cited a real-world example from 2007. When a new fleet of helicopters arrived with an aviation unit at a base in Iraq, some Soldiers took pictures on the flightline, he said. From the photos that were uploaded to the Internet, the enemy was able to determine the exact location of the helicopters inside the compound and conduct a mortar attack, destroying four of the AH-64 Apaches.
Geotagging leads to body bagging. It's the 21st century version of "Loose lips sink ships."
Needless to say, there are plenty of reasons to be wary on the domestic side as well. There's no good reason to broadcast to strangers the fact that no one is home.